Opendedup is a deduplication-based filesystem and block device designed to provide inline deduplication and flexiblity for applications. It benefits services such as backup, archiving, NAS storage, and Virtual Machine primary and secondary storage, and can be deployed in both a stand alone and distributed, multi node configuration. Standalone, it provides inline deduplication, replication, and unlimited snapshot capabilities. In a multi-node configuration, it adds global intra-volume deduplication, block storage redundancy, and block storage expandability. and will store and share unique data blocks with other volumes within the cluster. These volumes can also specify a level of redundancy for data stored in the cluster.

BZip2/OSS-QM is the OSS-QM project's branch of bzip2, which contains a lot of fixes not yet in the original upstream. The primary goal is to provide QM'ed/fixed versions of upstream releases, so they can be built and used without additional patches, especially in sysrooted crosscompiling environments.

Multicrush is a wrapper around pngcrush that distributes the work of brute-force compressing a single image over several pngcrush processes. This gets you a slightly less than a linear speedup, caused by different compression methods having slightly different durations. For example, the author has measured a speedup of 1.92 on a 2-core Intel T5300, and 3.86 on a 4-core Intel Q6600. The only requirements are a copy of pngcrush and at least Python 2.4. If you have version 2.6 or higher, multicrush can automatically detect how many CPUs to use.

Parallel XZ (pxz) is a compression utility that takes advantage of running XZ compression simultaneously on different parts of an input file on multiple cores and processors. This significantly speeds up compression time.

The ROHC library provides an easy and robust way for applications to reduce their bandwidth usage on network links with limited capacity or expensive costs. Headers of network packets are compressed with the ROHC protocol and algorithms. The ROHC protocol is very efficient for compressing VoIP streams which use RTP as a transport protocol. ROHC is also suitable for compressing IP-only (IPv4 or IPv6) flows, UDP flows, and many others.

S3QL is a file system that stores all its data online. It supports Amazon S3, Google Storage, and OpenStack and effectively provides you with a hard disk of dynamic, infinite capacity that can be accessed from any computer with Internet access. S3QL provides a standard, full featured Unix file system that is conceptually indistinguishable from any local file system. Additional features include compression, encryption, data de-duplication, immutable trees, and snapshotting, which make it especially suitable for online backup and archiving. The design favors simplicity and elegance over performance and feature-creep. Care has been taken to make the source code as readable and serviceable as possible. Solid error detection, error handling, and extensive automated test cases are provided.

MAF is a double-precision floating point number compressor. This package includes a program that can encode binary dump of double-precision floating point numbers into MAF format and decode the MAF-formatted image back to original double-precision numbers.